<template>
  <div ref="map" class="map"></div>
</template>

<script>
export default {
  mounted() {
    let {
      format: { OSMXML },
      Map,
      View,
      layer: { Tile: TileLayer, Vector: VectorLayer },
      source: { XYZ, Vector: VectorSource },
      style: { Circle: CircleStyle, Fill, Stroke, Style },
      loadingstrategy: { bbox: bboxStrategy },
      proj: { transformExtent },
    } = ol
    let map = null
    const styles = {
      amenity: {
        parking: new Style({
          stroke: new Stroke({
            color: "rgba(170, 170, 170, 1.0)",
            width: 1,
          }),
          fill: new Fill({
            color: "rgba(170, 170, 170, 0.3)",
          }),
        }),
      },
      building: {
        ".*": new Style({
          zIndex: 100,
          stroke: new Stroke({
            color: "rgba(246, 99, 79, 1.0)",
            width: 1,
          }),
          fill: new Fill({
            color: "rgba(246, 99, 79, 0.3)",
          }),
        }),
      },
      highway: {
        service: new Style({
          stroke: new Stroke({
            color: "rgba(255, 255, 255, 1.0)",
            width: 2,
          }),
        }),
        ".*": new Style({
          stroke: new Stroke({
            color: "rgba(255, 255, 255, 1.0)",
            width: 3,
          }),
        }),
      },
      landuse: {
        "forest|grass|allotments": new Style({
          stroke: new Stroke({
            color: "rgba(140, 208, 95, 1.0)",
            width: 1,
          }),
          fill: new Fill({
            color: "rgba(140, 208, 95, 0.3)",
          }),
        }),
      },
      natural: {
        tree: new Style({
          image: new CircleStyle({
            radius: 2,
            fill: new Fill({
              color: "rgba(140, 208, 95, 1.0)",
            }),
            stroke: null,
          }),
        }),
      },
    }
    const vectorSource = new VectorSource({
      format: new OSMXML(),
      loader: function (extent, resolution, projection, success, failure) {
        const epsg4326Extent = transformExtent(extent, projection, "EPSG:4326")
        const client = new XMLHttpRequest()
        client.open("POST", "https://overpass-api.de/api/interpreter")
        client.addEventListener("load", function () {
          const features = new OSMXML().readFeatures(client.responseText, {
            featureProjection: map.getView().getProjection(),
          })
          vectorSource.addFeatures(features)
          success(features)
        })
        client.addEventListener("error", failure)
        const query =
          "(node(" +
          epsg4326Extent[1] +
          "," +
          Math.max(epsg4326Extent[0], -180) +
          "," +
          epsg4326Extent[3] +
          "," +
          Math.min(epsg4326Extent[2], 180) +
          ");rel(bn)->.foo;way(bn);node(w)->.foo;rel(bw););out meta;"
        client.send(query)
      },
      strategy: bboxStrategy,
    })
    const vector = new VectorLayer({
      source: vectorSource,
      style: function (feature) {
        for (const key in styles) {
          const value = feature.get(key)
          if (value !== undefined) {
            for (const regexp in styles[key]) {
              if (new RegExp(regexp).test(value)) {
                return styles[key][regexp]
              }
            }
          }
        }
        return null
      },
    })
    const attributions =
      '<a href="https://www.maptiler.com/copyright/" target="_blank">&copy; MapTiler</a> ' +
      '<a href="https://www.openstreetmap.org/copyright" target="_blank">&copy; OpenStreetMap contributors</a>'
    const raster = new TileLayer({
      source: new XYZ({
        attributions: attributions,
        url:
          "https://api.maptiler.com/tiles/satellite/{z}/{x}/{y}.jpg?key=" +
          mapkeys.maptiler,
        maxZoom: 20,
      }),
    })
    map = new Map({
      layers: [raster, vector],
      target: this.$refs.map,
      view: new View({
        center: [739218, 5906096],
        maxZoom: 19,
        zoom: 17,
      }),
    })
  },
}
</script>